The contribution of chemistry industry to ‘Sustainable Development’ was demonstrated by the utilization of renewable raw materials, (Meier, et al., Chem. Soc. Rev., 2007, 36, 1788-1802; Baumann, et al., Angew. Chem. Int. Ed. Engl. 1998, 27, 41-62; Biermann, et al., Angew. Chem. Int. Ed. 2000, 39, 2206-2224; and Khot, et al., Journal of Applied polymer Science, 2001, 82, 703-723.), such as polysaccharides, natural oils and fats, etc. In coating science, drying oils, which are naturally occurring triglycerides of unsaturated fatty acids, have been used in the formulation of coating resins for centuries. Currently, some innovative design strategies in this area were employed such as the fatty acids reacted with hyperbranched polyols (Bat, et al., Progress in Organic Coatings, 2006, 55, 330-336; Mańczyk, et al., Progress in Organic Coatings, 2002, 44, 99-109; Karakaya, et al., Progress in Organic Coatings, 2007, 59, 265-273; and Haseebuddin, et al., Progress in Organic Coatings, 2009, 64, 446-453) (i.e. di-pentaerythritol, tri-pentaerythritol or derivatives) to obtain high solids alkyd resins, based on concepts of structure-property relationships.
Sucrose is a naturally occurring raw material having eight hydroxyl groups, which potentially can be attached by eight fatty acids to yield the desired well-defined compact ester structure. Sucrose esters of unsaturated fatty acids (SEUFA) were explored as coating vehicles in the 1960s. Bobalek, et al., Official Digest, 1961, April, 453-468; and Walsh, et al., Div. Org. Coatings Plastic Chem., 1961, 21, 125-148. These early studies also indicated that the highly substituted SEUFA had a uniform fatty acid distribution, low viscosity, rapid air-drying time and good coating properties. Procter & Gamble developed an efficient industrial process for SEUFA synthesis that yields complete substitution of all eight hydroxyls on sucrose. U.S. Pat. Nos. 6,995,232; 6,620,952; and 6,887,947.
To build up better polyester/alkyd resins, acetoacetates have been used because of their attractive attributes, such as low glass transition temperature, high solid content, and selective crosslinking options. Kuo et al., (U.S. Pat. Nos. 6,794,049 and 6,780,523), disclosed both high solids solventborne and waterborne air curable coating compositions based on acetoacetate-functional alkyd resins, prepared by transesterification reaction. Bors et al., (U.S. Pat. No. 5,484,849), disclosed an air curing polymer with pendant acetoacetate functional groups, prepared by free radical polymerization (emulsion polymerization). The acetoacetate functionalized alkyds, in combination with at least one drier, cured faster than the original alkyds in air-drying process, without the evidence of reaction mechanism. As the other options, acetoacetate functionalized resins can be cured by enamine formation (Trevino, et al., Progress in Organic Coatings, 2002, 44, 49-54; Esser, et al., Progress in Organic Coatings, 1999, 36, 45-52; Geurink, et al., Progress in Organic Coatings, 1996, 27, 73-78; and Geurink, et al., Progress in Organic Coatings, 2003, 48, 153-160) with multifunctional amines, Michael addition with acrylates (Vogt-Birnbrich, Progress in Organic Coatings, 1996, 29, 31-38; and Pieschmann, et al., Progress in Organic Coatings, 1999, 36, 64-69), and reaction with aldehyde, (Pieschmann, et al., Progress in Organic Coatings, 1999, 36, 64-69).